Equivalent weight of Potassiumpermaganate in strong alkaline medium is

Options

A. `("molar mass")/(5)`
B. `("molar mass")/(3)`
C. `("molar mass")/(2)`
D. molar mass itself.

Answer

To find the equivalent weight of potassium permanganate (KMnO4) in a strong alkaline medium, we can follow these steps:

### Step 1: Identify the Reaction
In a strong alkaline medium, potassium permanganate reacts as follows:
\[ 2 \text{KMnO}_4 + 2 \text{KOH} \rightarrow 2 \text{K}_2\text{MnO}_4 + \text{H}_2\text{O} + \text{O} \]

### Step 2: Determine the Change in Oxidation State
In this reaction, the oxidation state of manganese (Mn) changes from +7 in KMnO4 to +6 in K2MnO4.

### Step 3: Calculate the Change in Oxidation State
The change in oxidation state of manganese can be calculated as:
\[ \text{Change in oxidation state} = +7 - (+6) = +1 \]

### Step 4: Use the Formula for Equivalent Weight
The equivalent weight (EW) can be calculated using the formula:
\[ \text{Equivalent Weight} = \frac{\text{Molar Mass}}{\text{Change in Oxidation State}} \]

### Step 5: Substitute the Values
Since the change in oxidation state is +1:
\[ \text{Equivalent Weight} = \frac{\text{Molar Mass}}{1} = \text{Molar Mass} \]

### Step 6: Conclusion
Thus, the equivalent weight of potassium permanganate in a strong alkaline medium is equal to its molar mass.

### Final Answer
The equivalent weight of potassium permanganate (KMnO4) in strong alkaline medium is the molar mass itself.